51,073 research outputs found
The study of the charged top-pion decay processes
In the framework of top-color assisted technicolor(TC2) theory, we study the
four decay processes of charged top-pion, i.e.,
, , , , the decay branching ratio of these
modes are calculated. The results show that the main decay channels of charged
top-pion are the tree level modes: and . Light is easier to be detected than heavy one at future
coliders. So, the study provides us some useful information to search for
charged top-pion.Comment: 14 pages, 6 figure
Magnetic field suppression of Andreev conductance at superconductor-graphene interfaces
Studying the interplay between superconductivity and quantum magnetotransport
in two-dimensional materials has been a topic of interest in recent years.
Towards such a goal it is important to understand the impact of magnetic field
on the charge transport at the superconductor-normal channel (SN) interface.
Here we carried out a comprehensive study of Andreev conductance under weak
magnetic fields using diffusive superconductor- graphene Josephson weak links.
We observe that the Andreev conductance is suppressed even in magnetic fields
far below the upper critical field of the superconductor. The suppression of
Andreev conductance depends on and can be minimized by controlling the ramping
of the magnetic field. We identify that the key factor behind this suppression
is the reduction of the superconducting gap due to the piling of vortices on
the superconducting contacts. In devices where superconducting gap at the
superconductor-graphene interface is heavily reduced by proximity effect, the
enlarged vortex cores overlap quickly with increasing magnetic field, resulting
in a rapid decrease of the interfacial gap. However, in weak links with
relatively large effective superconducting gap the AR conductance persists up
to the upper critical field. Our results provide guidance to the study of
quantum material-superconductor systems in presence of magnetic field, where
'survival' of induced superconductivity is critical.Comment: 22 pages, 4 figures. Typos corrected, reference adde
Constraining the Equation of State of Neutron Stars through GRB X-Ray Plateaus
The unknown equation of state (EoS) of neutron stars (NSs) is puzzling
because of rich non-perturbative effects of strong interaction there. A method
to constrain the EoS by using the detected X-ray plateaus of gamma-ray bursts
(GRBs) is proposed in this paper. Observations show some GRB X-ray plateaus may
be powered by strongly magnetized millisecond NSs. The properties of these NSs
should then satisfy: (i) the spin-down luminosity of these NSs should be
brighter than the observed luminosity of the X-ray plateaus; (ii) the total
rotational energy of these NSs should be larger than the total energy of the
X-ray plateaus. Through the case study of GRB 170714A, the moment of inertia of
NSs is constrained as , where is the critical
rotational period that an NS can achieve. The constraint of the radii of NSs
according to GRB 080607 is shown in Table 1.Comment: 6 pages, 2 figute, The Astrophysical Journal, 886:87, 2019 December
1, https://doi.org/10.3847/1538-4357/ab490
Quantifying the efficiency of price-only contracts in push supply chains over demand distributions of known supports
In this paper, we quantify the efficiency of price-only contracts in supply chains with demand distributions by imposing prior knowledge only on the support, namely, those distributions with support [a, b] for 0 < a <_ b < +1. By characterizing the price of anarchy (PoA) under various push supply chain configurations, we enrich the application scope of the PoA concept in supply chain contracts along with complementary managerial insights. One of our major findings is that our quantitative analysis can identify scenarios where the price-only contract actually maintains its efficiency, namely, when the demand uncertainty, measured by the relative range b/a, is relatively low, entailing the price-only contract to be more attractive in this regard
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